1. Field of the Invention
The present invention relates to an optical pickup, and more particularly, to a method of dissipating heat from an optical pickup, to efficiently reduce heat from a heat source, and an apparatus for the same.
2. Description of the Related Art
In general, an optical pickup of an optical disk driver is a driving element to record and reproduce peaks or marks on and from a disk. An increase in a temperature of an optical pickup, a laser diode, or other heat sources deteriorates a reproducing quality when reproducing, increases a wavelength of a laser and thereby reduces an ability to perform a high speed recording, and generates a large jitter when recording. Since the optical pickup of the optical disk driver includes a laser diode, a hologram optical device, and a photodiode, it is required to maintain an internal temperature of the optical pickup lower than a predetermined level, to perform stable recording and reproducing.
But as the size and the weight of the optical disk driver are decreased, a conventional passive method of reducing an internal temperature of an optical pickup, such as natural thermal conduction and convection, cannot reduce the internal temperature sufficiently. In particular, heat from a laser diode and a photodiode, which are necessary elements for recording and reproducing, largely affects the performance of an optical pickup. The most general method of reducing the internal temperature of an optical pickup is by dissipating the heat from the laser diode and the photodiode through thermal conduction and convection using a cooling fin or a cooling plate connected directly to the laser diode and the photodiode.
But such a conventional method of dissipating heat through thermal conduction and convention using the cooling fin or the cooling plate is insufficient to effectively reduce the internal temperature of an optical pickup. In other words, as the size and the weight of a driver decrease, the conventional passive method of natural thermal conduction and convection using the cooling fin or the cooling plate cannot properly reduce the internal temperature of an optical pickup. Accordingly, the increase in the temperature still occurs, resulting in the increase in jitter and deterioration of reproducing quality due to misalignment of detection portions of a main beam and a side beam of a photodiode.
In addition, due to the increase in temperature, a laser wavelength is changed as well as lowering a laser power when recording, thus a stable recording cannot be performed.